This invention relates to a steel frame shearing apparatus suitably employed for shearing off shaped steel materials, steel frames in concrete structures and steel body frames when demolishing automobiles.
Hitherto, as the shearing apparatus of the above type, there have been proposed crushing type apparatus in which opposing blades crush and pinch off workpieces and scissors type apparatus in which opposing shearing blades shear off workpieces. In shearing by the use of opposing blades, the opposing blades require a substantial force in shearing off workpieces and the cutting edges of the blades tend to nick easily. And since workpieces tend to slip towards the leading ends of the blades, the blades need to have a length sufficient to accommondate the slippage of workpieces. In shearing by the use of shearing blades, when workpieces of limited thickness are to be sheared off, the workpiece is caught in between the shearing blades and when workpieces of considerable thickness are to be sheared off, the blades tend to slip laterally from the workpieces, and thus the apparatus cannot shear off workpieces satisfactorily. In short, a shearing apparatus with shearing blades is suitably employed only for shearing-off workpieces which can be accommodated by the blades and thus, the application and performance of such shearing apparatus are limited. Further, in this type of shearing apparatus, there is also the problem that workpieces slip towards the leading ends of the blades.